Child resistant unit dose pack

ABSTRACT

The present invention provides a child resistant blister pack for packing pharmaceutical solid dosage form comprising a blister sheet having a pattern of cavities/blisters, a rupturable cover foil laminated to the blister sheet covering and sealing the blisters and blister sheet containing the unit dosage forms is enfolded into a non-tearable paper/laminate card with an intrinsic pressure-sensitive permanent acrylic/rubber based adhesive, a polymeric film/laminate containing an intrinsic pressure-sensitive permanent acrylic/rubber based adhesive is placed on a non-tearable paper/laminate card in a precise manner, such that it corresponds with the individual cavities of the blister.

FIELD OF THE INVENTION

The present invention relates to child resistant packs. In particular, the present invention relates to an improved child resistant unit dose pack with retention of child resistance feature upto last dose. The invention has been developed primarily for packing pharmaceutical solid dosage forms and will be described hereinafter with reference to this application. More precisely, it relates to child resistant, tamper resistant cavity/blister pack for solid dosage forms such as pharmaceutical tablets, capsules, candies, gums, lozenges (hereinafter collectively referred as tablets) etc. However, it will be appreciated that the invention is not limited to this particular field of use.

BACKGROUND OF THE INVENTION

Any discussion of the prior art throughout the specification should in no way be considered as an admission that such prior art is widely known or forms part of the common general knowledge in the field.

Packs for small goods come in a variety of sizes, with various special features. Most pharmaceutical packs are either plain hard paper/board cartons or layered blisters of aluminum/aluminum or aluminum/plastic [polyvinyl chloride] sheets. Blister packages of the type employed for packaging medication in solid form typically comprise a first sheet of transparent or translucent thermoformable material such as polyvinyl chloride or polystyrene having a plurality of flexible cavities/bubbles/blisters preformed therein and projecting outwardly from one surface to define separate compartments for individual doses of medicine, typically a single tablet, and a cover sheet of reputable material such as aluminum foil or paper bonded to the first sheet and overlying and covering and thereby closing the open cavities/bubbles/blisters. While such packages have provided efficient and effective packaging of individual dosages of medicament in tablet form, such packages are not child proof or child resistant, and present a potential hazard to small children. While the known child resistant blister packages have been effective, at least to some degree, in preventing access to the packaged medicament by young children, they have not been entirely satisfactory for a number of reasons. For example, some of the packages, while being child resistant initially, do not retain the desired degree of child resistance after a portion of the product has been dispensed. Also, product packages in some of the child resistant packages have not been as readily accessible to adults as desired, particularly those with loss of manual dexterity. Further, some of the known packages have been relatively expensive to manufacture and/or assemble.

To render the typical blister package more child resistant, a number of packages have been devised which include additional features intended to render the package difficult for small children to open while at the same time being user friendly for adults including adults who have suffered some loss of manual dexterity.

U.S. Pat. No. 6,161,699 discloses an improved child resistant package comprising A blister sheet having a pill receiving blister cavity, rupturable lidding foil laminated onto the other surface of said blister sheet, said lidding foil extending over and sealingly closing said blister cavity, a backing card having one surface overlying and adhesively bonded to said lidding foil, with a punch out section being defined by a weakened score line in the backing card and a thin film of high strength, flexible material adhesively bonded to the other surface of the said backing card, said film extending over said punch out section and at least a portion of the backing card surrounding the said punch out section said thin film being bonded to said card by low peel strength adhesive whereby the thin film can be manually pulled off by an adult but can not readily be pulled off by a child.

U.S. Pat. No. 4,537,312 (EPO162378) discloses a child resistant blister pack wherein the product to be dispensed is enclosed in a blister packet, which in turn is enclosed in further packaging having tabs therein, the packaging child-resistant features while also being tamper-evident, without an additional resealable film/layer.

U.S. Pat. No. 4,988,004 discloses a child resistant blister pack wherein the blister pack does not have a resealable film/layer. The patent discloses a pack having a reinforced backing sheet which separates into strata on tearing and adhered to a rupturable film closing article containing pockets. The backing sheet is provided with tabbed tear strips overlying the pockets. On tearing the tear strips separate into strata indicating that opening has been started.

U.S. Pat. No. 5,046,618 discloses a pack having a blister film sheet with depressions with a lidding sheet and perforated to provide lines of weakness to define single dosage units with a depression containing a dosage form in each dosage unit. After tearing along the perforations, a single dosage unit is separated from the blister pack. The user may then access the single-dosage form in the associated single-dosage unit.

U.S. Pat. No. 5,758,774 discloses a blister package which can be converted from child-resistant to non-child-resistant at the user's discretion. A slit is provided in each package for enabling access to an individual blister and a section the package can be removed to provide access to a tearaway perforated strip for providing access to a row of blisters. Alternatively, a tearaway perforated strip can also be provided for enabling access to an individual blister.

U.S. Pat. No. 6,659,280 discloses a pack wherein the blister package has a single blank sheet with a first and second opposing side edges and first, second, and third score lines that are parallel to the first and second opposing side edges. The opposing side edges and score lines delimit a back panel, first and second intermediate panels, and a top panel having at least one blister receiving pocket. The first intermediate panel is folded onto the back panel about the first score line. The second intermediate panel is folded onto the first intermediate panel about the second score line. The top panel is folded onto the second intermediate panel about the third score line. A cavity through which the article passes is defined at least by the first and second intermediate panels. The back panel includes a tear away panel positioned remote from an outer periphery of the package.

U.S. Pat. No. 6,776,285 discloses a pack wherein a blister pack comprises a sheet-like thermoformed body having a number of protrusions extruded from a surface of the body; and a laminated film made from a synthetic resinous material, which closes openings of recesses on a reverse face of the thermoformed body after to-be-packaged matters have been placed in the recesses, each recess forming an interior of each protrusion, wherein the laminated film is bonded to the thermoformed body with a small bonding strength to be capable of peeling, and a cut is formed in a position surrounding the opening of each recess such that the cut penetrates the laminated film in its thickness direction from its reverse face but does not penetrate the body in its thickness direction.

US Patent Application No. 2003/0006163 discloses a child resistant blister pack formed by three portions which are formed from a single sheet of suitable card or plastic. The first and third portions form an outer envelope folded over the second portion. The apertures in this embodiment are co-related and the penetrable lid is exposed.

The pack as per the present invention in its preferred embodiment by unique use of component materials and their contraction/manipulation, restrict access of the unit dosage forms to children. Further, the pack does not permit access by children to the enclosed unit dosage forms even when part of the package has been dispensed (i.e. some of the dosage forms have been accessed by an adult). Thus the effect of a child attracted to a pack which she or he has observed an adult partaking of some ingestible substance; and therefore trying to gain access to the same; is addressed by the current pack.

OBJECTS OF THE INVENTION

It is an object of the present invention to overcome or ameliorate at least one of the disadvantages of the prior art, or to provide a useful alternative.

It is yet another object of the present invention to provide an improved, inexpensive, child resistant blister package for medicaments.

Another object is to provide such a blister package that retains its child resistant feature intact after each dosage use.

SUMMARY OF THE INVENTION

According to the invention, there is provided an improved child resistant pack with a peelable polymeric layer. In accordance with the present invention, child resistant pack comprises a blister sheet having a pattern of cavities/blisters formed therein for receiving individual tablets or pills and a rupturable cover foil laminated to the blister sheet covering and sealing the blisters. According to the present invention, the Blister sheet may be made of polyvinyl chloride or other suitable material and may be thermoformed or die formed to create series of cavities/blisters. The tablets/pills are deposited in the said cavities/blisters. The blister sheet containing pills/tablets are limited with a rupturable cover foil laminated to the blister sheet covering and sealing the blisters. The cover foil is preferably made of aluminum foil or paper, which may be ruptured to dispense the pill/tablets by convention method.

According to the present invention, the blister sheet containing the unit dosage forms is enfolded into a non-tearable paper/laminate card with an intrinsic pressure-sensitive permanent acrylic/rubber based adhesive in such a manner that the blister pack containing the unit dosage forms is wholly enveloped within the non-tearable paper/laminate from one side (the side covered by the rupturable side) and visible from the other side (the side comprising the cavities in the blister sheet and containing the unit dosage forms).

Corresponding to the side covering the rupturable cover foil, an area of the non-tearable paper/laminate card corresponding to each cavity of the blister pack has perforation lines formed therein, through which the respective unit dosage form can be pushed through from the opposite side and accessed. To restrict this access, a polymeric film/laminate containing an intrinsic pressure-sensitive permanent acrylic/rubber based adhesive is placed in a precise manner, such that it corresponds exactly with the individual cavities of the blister. To permit access by an adult, the areas of the film corresponding to the individual cavities are perforated in such a manner as to permit peeling off of the portion of the film/laminate corresponding with one particular blister cavity at a time and starting from one corner may be topmost or bottom most and without disturbing the portion overlying the remaining perforations.

This pack is particularly child resistance and child cannot easily excess the dosage. While removing the tablet form the package according to the present invention, the film is moved away from a single cavity/blister and that single cavity/blister pressed against the paper/laminate card from the opposite side, such that the first tearable cover foil tears, and then the paper/laminate card is torn open, and a tablet is released.

BRIEF DESCRIPTION OF THE DRAWINGS

Other features and advantages of the invention will be apparent from the detailed description contain herein below, taken in conjunction with the drawings, in which:

FIG. 1 is a side view of a pack according to the invention.

FIG. 2 is a cross section of individual blister unit, according to the invention.

FIG. 3 is a plane view of inside of the pack according to the invention.

FIG. 4 is a plane view of outside of the pack with peelable polymeric layer/laminate, according to the invention.

The pack generally shown by the reference number, which comprises of

-   1—Peelable polymeric film/laminate -   2—Intrinsic pressure sensitive adhesive from Peelable polymeric     film/laminate 1 -   3—Non tearable paper -   4—Intrinsic pressure sensitive permanent acrylic/rubber based     adhesive (between non-tearable paper & aluminium foil) -   5—Aluminium foil -   6—Poly Vinyl Chloride/Poly Vinyl Di Chloride Film -   7—Intrinsic pressure sensitive permanent acrylic/rubber based     adhesive (between poly vinyl chloride/poly vinyl dichloride film &     non-tearable paper) -   8—Non tearable paper -   9—Die-cut perforation into polymeric film and intrinsic pressure     sensitive adhesive 2 -   10—Die-cut perforation into outside non-tearable paper 3 -   11—Individual punch cut on outside of non-tearable paper 3 for unit     tablets dispensing -   12—Perforation along with the crease line on inside non-tearable     paper 8 -   13—Tablets & Capsules -   14—Individual perforation on polymeric film/laminate, which covers     perforation 11 -   15—Individual polymeric stickers (covering unit dose) -   16—Individual blister cavity

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

A preferred embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawings in which:

Although the invention has been described with reference to specific examples, it will be appreciated by those skilled in the art that the invention may be embodied in many other forms.

According to the preferred embodiment of the present invention and referring to FIGS. 1, 2, 3 & 4, an efficient child resistant package for pharmaceuticals in solid dosage form comprising a blister sheet by reference numerals 6 having a pattern of cavities blisters 16 formed therein for receiving individual tablet/pills 13. The blister sheet 6 of the present invention may be made of poly vinyl chloride or poly vinyl dichloride film or any of the variety of the blister films or products which have been approved by the FDA, including films or aluminum foil which are die formed or otherwise shaped to provide the blisters. The blister sheet 6 is laminated by a tearable push through cover foil 5, preferably made of an aluminum foil by such a way that it covers and seal the cavity 16.

It can be transparent or translucent, depending upon the effect of light on the drug being used in the tablet. Optionally, cavities/blisters formed on the blister sheet 6 may have various shapes, usually corresponding to the shape of the tablet/capsule 13. So the blister sheet 6 may have circular cavities/blisters for circular tablets, and oval or polygonal shapes for capsules/tablets of that shape. These blisters can be formed according to specific shapes such as columns for showing usage of tablets over a period of time, for e.g. a blister sheet 6 having a series of twenty eight or thirty cavities/blisters or as per dosage form arranged in a seven tablet per column manner and remaining tablets in a separate column.

A non tearable paper/laminate card 3 is glued/laminated to the cover foil (aluminum foil) 5 such that it has individual perforation lines corresponding to the shape of the cavity/blister 16. Finally a peelable polymeric film 1 of flexible material is glued/laminated to the non-tearable paper 3 by using Intrinsic pressure sensitive adhesive 2 from Peelable polymeric film/laminate 1.

The peelable polymeric film 1 covers the perforations and an area of non tearable paper/laminate card 3 adjacent to each aperture, and optionally has perforation lines formed therein separating; the areas overlying each perforations to enable the peelabele polymeric film/laminate 1 to be removed from the space of the package overlying the individual perforations without disturbing the portion overlying the remaining perforations.

This peelable polymeric film/laminate 1 may be glued/laminated to the non-tearable paper 3 either completely or in parts in a variety of shapes depending on the functionality/requirements of the entire package.

Further referring to FIGS. 1 and 2 together, the cavity/blister 16 can be arranged in parts such a way 17 to form a group of seven blisters for weekly use.

The tearable push through cover foil, preferably aluminum foil 5 laminated to the blister sheet (plastic materials) 6 is made up of aluminum foil or similar materials used and accepted in the pharmaceutical industry.

The non-tearable paper 3 is made of strong paper or board materials. Optionally, a second laminate/paper card 8 is pasted on to the top of the blister sheet 6, such that the blister sheet 6 containing the tablet is encased between two laminate/paper cards 3 & 8.

Alternatively, a single laminate/non-tearable paper card 3 is folded to wrap around a blister sheet 6. In either case the second laminate/paper card 8 will have a gap/hole corresponding to the individual cavities/blisters 16 so that the individual cavities/blisters protrude out of gap/hole and are visible to the user. The laminate/paper card 3 & 8 may have instructions printed on one or both the sides. The paper card 3 in one embodiment may have a laminated surface 2 on one side only. It is to be noted that lamination is not an essential requirement of the laminate/paper card 3 & 8 and a strong non tearable paperboard can equally serve the purpose.

Referring to FIGS. 1 and 2 together in one embodiment, the laminate/paper card 3 has marks/perforations 14 dividing the pack into a number of parts 15. The peelable polymeric film 1 is permanently glued at area so that it corresponds with the marks/perforations on the laminate/nontearable paper 3, due to the non-lamination of the paper card 3. The peelable polymeric film 1 may have perforations 14 & similar to part 15. The peelable polymeric film 1 is removable along the perforations 14.

Referring to FIGS. 1 & 2, the peelable polymeric film 11 of flexible material can be made of a variety of materials, including plastics. There can be a single film 1 covering an entire column. Optionally, the peelable polymeric film 1 covering the perforations is actually a series of separate stickers for each cavity/blister 16. These separate stickers can be of any shape, preferably non-polygonal in shape such as a circular or oval/elliptical, similar to the shape of the cavity. Optionally, the single peelable polymeric film 1 per column can be modified so that the film 1 may have individual perforation lines separating the individual cavities/blisters 16 so that a part of the peelable polymeric film 11 can be torn apart from the peelable polymeric film 1 series. In this case i.e. separate stickers embodiment, the peelable polymeric film 1 need not be resealable.

When a tablet is to be removed, the peelable polymeric film 1 is moved away from a single cavity/blister 16 and that single cavity/blister is pressed against the non-tearable paper/laminate card 3 towards the film 1 side, such that the first tearable cover foil (aluminium foil) 5 tears, and then the non tearable paper/laminate card 3 is torn open along the perforation, and finally a tablet 13 is released.

It is to be noted that though the preceding discussion was with reference to a tablet, this pack can be equally effectively used with other solid/semi-solid items such as capsules, gums, candies etc.

The perforations on non-tearble film/laminate on outer side of the card, where Peelable polymeric film/laminate 1 is stuck, plays very important role in developing child resistant pack. The inventor has obtained the perforation pattern as 4 to 6 cuts and 4 to 6 bridges on non-tearble film/laminate 3 which provides most obtimum child resistance. Lesser cuts and bridges than this leads to lesser child resitance and more cuts and bridges than this leads to very high child resitance but poor opening by an adult patient.

The inventor also has found that to have a user friendly pack whereby patient can use the pack as a pocket device or unit, it is necessary to have certain size of the pack to fit into the typical shirt pocket. To ensure this, inventor has obtained a folded pack with crease in the middle so that pack operates like a book. To impart child resistance to such a pack, inventor has made perforations along the folding length of the middle of the pack, but left our perforation in the end for almost 2-10 mm at top and bottom of the pack. This ensures that a child trying to tear the pack from the middle will not be able to do so since perforations tart only 2-10 mm from pack edge.

In one of the embodiment, pack may contain nightglow system like colored fluorescent printing to impart self-glowing in the night. This enables especially elderly patients to locate the pack in poorly lit room conditions or areas for nighttime administration. 

1. A child resistant blister pack for packing pharmaceutical solid dosage form comprising a blister sheet, having cavities for the retention of dosage form, being sealed by tearable push through cover foil or layer, a non-tearable laminated paper card having pattern of perforations, wherein the card containing the blister is partially perforated from inside and creased from outside and said card is glued or laminated to the cover foil and a peelable film of flexible material being glued or laminated to the card.
 2. A child resistant blister pack according to claim 1, wherein the number of the perforations on non-tearable film/laminate on outer side of the card are in the perforation pattern of 4 to 6 cuts and 4 to 6 bridges on non-tearable film/laminate 3 which provides most optimum child resistance. Lesser cuts and bridges than this leads to lesser child resistance and more cuts and bridges than this leads to very high child resistance but poor opening by an adult patient.
 3. A child resistant blister pack according to claim 1 wherein said perforations along the folding length of the middle of the pack, but left our peration in the end for 2 to 10 mm at top and bottom of the pack.
 4. A blister pack in accordance with claim 1, wherein peelable polymeric film covering aperture and area around aperture has perforation lines separating areas overlying each perforation to enable the peelable film for each tablet to be removed
 5. A blister pack in accordance with claim 1, where blister sheet may be made up of poly vinyl chloride or poly vinyl dichloride or similar conventional material, of transparent or transluscent or opaque nature and cavities or blisters formed on such blister sheet can be of various different shapes and numbers.
 6. A blister pack in accordance with claim 1, where pack may contain nightglow system like colored fluorescent printing to impart self-glowing in the night.
 7. A child resistant blister pack for packing pharmaceutical solid dosage form comprising a blister sheet having a pattern of cavities/blisters, a rupturable cover foil laminated to the blister sheet covering and sealing the blisters and blister sheet containing the unit dosage forms is enfolded into a non-tearable paper/laminate card with an intrinsic pressure-sensitive permanent acrylic/rubber based adhesive, a polymeric film/laminate containing an intrinsic pressure-sensitive permanent acrylic/rubber based adhesive is placed on a non-tearable paper/laminate card in a precise manner, such that it corresponds with the individual cavities of the blister. 